The invention relates to a hair-shaping appliance, in particular steam styling tongs.
JP-A-11 46839 discloses a gas-operated hair-shaping appliance, in which flame-free combustion of a gas takes place by means of a catalyst for heating up heating tubes in a combustion chamber. There is provided a steam-distributor chamber which is supplied with water by a liquid container. The liquid container is provided with an exchange valve, via which air flows in when water flows out of the liquid container. When not in use, the pressure in the liquid container can increase, for example, on account of heating. This may result in water passing, via the liquid-channeling device, into the steam chamber and, from there, then flowing into the steam-distributor chamber, where it ultimately passes outward via the through-passages. During the heating-up operation of the hair-shaping appliance, this may result in an increased formation of steam. Thus, a user may sustain burns if he/she picks up the appliance.
Outlets connected to the combustion chamber and through-passages connected to the steam-distributor chamber are formed in the drum. This may result in differing temperatures at various locations, since the temperature at the outlets is usually higher than the temperature at the through-passages. Furthermore, this hair-shaping appliance is expensive and complex to construct as a result of the combustion chamber being separated from the steam-distributor chamber.
An object of the invention is to develop a gas-operated hair-shaping appliance, in particular steam styling tongs, according to the preamble of patent claim 1 such that the above disadvantages are avoided and, at the same time, the construction and the assembly of the hair-shaping appliance are simplified and the production costs are reduced. Aspects of the invention are also intended to achieve uniform and/or freely selectable steam distribution over the circumference of the drum.
In one aspect of the invention the steam can mix with the combustion gases coming from the catalyst to better effect in one common chamber and can heat up more uniformly. The steam and combustion gases pass out through commonly used through-passages, which may be formed uniformly around the drum. This results in a uniform hot stream of steam around the drum. In this way, the drum or the heating tube is also heated up better and more uniformly, because the common chamber can bound the drum all the way round from the inside. In order that no water passes into the common chamber, suitable means are provided according to an aspect of the invention. This is because if water droplets were to wet the catalyst, then considerable ignition problems would arise since a comparatively high level of ignition energy would have to be applied in order for the water located on the catalyst to be evaporated before the flame-free combustion process ignites the catalyst. A single collecting chamber for the combustion gases and the steam simplifies the construction of the hair-shaping appliance to a considerable extent and, in addition to the abovementioned advantages, reduces the production costs.
By virtue of the features of one embodiment, only through-passages are formed on the drum. The through passages are connected to the common chamber. Both the hot combustible gases and the steam pass through the through-passages, in the form of a mixture.
The features of another embodiment include means to prevent excess water from collecting in the evaporating device because, during the return stroke of the dosing device, the excess water is automatically sucked back into the liquid container. Even when the dosing device is actuated a number of times in quick succession, these actuations cannot result in the evaporating device overflowing since during the return stroke of the dosing or pumping device, on account of the xe2x80x9cclosedxe2x80x9d liquid tank, excess water is always sucked back into the water tank via the liquid-channeling device. As a result of this embodiment of the invention, the appliance remains dry and no water can penetrate into the catalyst via the common chamber or pass out of the drum. Penetrating water would impair the functioning of the catalyst or would even prevent it from being ignited, since it would be necessary to first evaporate the water in the catalyst. The energy required to do this, however, is not present at the start of ignition.
According to the features of another embodiment, the dosing device comprises, on the one hand, a pressure/suction pump and, on the other hand, a closed liquid container with only one outlet. During the return stroke of the dosing or pumping device, the outlet performs the function of an inlet for excess water which collects in the evaporator chamber or still adheres to the liquid-channeling device as an excess droplet. Of course, it is also conceivable to integrate a further liquid container in the appliance, which is provided with a separately working liquid-channeling device that channels excess water back into the second container.
By virtue of excess liquid flowing back immediately into the liquid container from the evaporating device, the hair-shaping appliance can be held as desired in a user""s hand without liquid passing out of the drum via the through-passages. This also results in a particularly economical water-discharging device. The liquid located in the liquid container is fully converted into steam without some of the water running out of the appliance unused.
The features of another embodiment are provided in order to improve the operation of the evaporating device further, and in order to prevent the water that is discharged by the dosing device during the actuation from escaping even when the hair-shaping appliance is in the horizontal position. The evaporator chamber forms a relatively large evaporating surface and, at the same time, it retains small water droplets to better effect. It is possible here for the chamber to be of plate-like, cup-like or pot-like design.
The features of another embodiment result in an embodiment of liquid-channeling device which does not expose the wick to an excessively high temperature. This increases the service life of the wick. It is thus no longer necessary for the wick to be pressed against the evaporating surface in order for water to be discharged in a metered manner. However, it is also possible, upon actuation of the dosing device, for the wick to come into contact with the evaporator plate and to be pressed against it slightly.
The features of another embodiment make it possible for the wick to transport both liquid and air in both directions. This arrangement allows straightforward metering of the liquid. It is not possible for the liquid to run out without the dosing device being actuated.
The features of another embodiment provide a large receiving surface for the liquid on the wick, with the result that, even when the liquid container is in the horizontal position, the wick is still supplied with sufficient liquid. This holds true even when the liquid container is almost empty.
The features of another embodiment render the distance between the free end of the wick and the evaporator-chamber surface small enough to enable, even in the case of a small droplet forming at the free end of the wick, for the droplet to come into contact with the evaporator-chamber surface and even to flow out onto the latter, and evaporate there.
The features of another embodiment bring about a particularly straightforward integration of the dosing device with the liquid container. Based on the piston stroke, a correspondingly large or small amount of liquid passes out of the liquid-channeling device. In the case of this arrangement, the piston has to be displaced automatically into its starting position, preferably by means of a spring, in order to enable an automatic suction stroke to be executed.
The features of another embodiment result in a particularly straightforward embodiment of the dosing device integrated in the liquid container. The elastically deformable wall can easily be actuated for discharging liquid; however, it also easily moves back automatically into its original shape again, on account of its elastic expandability, in order to allow the suction stroke to be executed without a user""s intervention. The elastically deformable wall may be fastened on the liquid container, for example by injection molding, screw connection, adhesive bonding or in some other manner. It may also be designed as a molding with the liquid container. Although, in this case, the wall thicknesses should be coordinated with one another such that, upon actuation of the deformable wall, the liquid container itself hardly deforms.
In order that the dosing device can discharge considerable quantities of liquid, it is advantageous if the deformable wall is of an outwardly curved design. The elastically deformable material and the wall thickness of the deformable wall have to be selected such that, on the one hand, they can easily be moved by hand and, on the other hand, they produce a sufficient suction-stroke action in the chamber of the liquid container such that excess water, which may be present in the evaporating chamber or on the wick, can be sucked back into the liquid container sufficiently quickly via the liquid-channeling device.
The features of another embodiment are provided in order to ensure that water only flows into the evaporating chamber when the liquid-channeling device butts against the base of the evaporating chamber or, better, terminates a short distance in front of the chamber. The rigidity of the elastically deformable wall is thus selected to be high enough for the liquid container, initially without any marked elastic deformation of the wall, to be displaced counter to the force of the compression spring until the wick has reached its liquid-discharging position in the evaporating chamber. This ensures that even excess liquid which may occur during the return stroke can be channeled back into the liquid container via the wick. For easy displacement of the liquid container, the latter is fastened in a non-displaceable manner in an insulating sleeve, which is fastened in a stationary manner within the drum. In order to avoid thermal overloading of the liquid container, the insulating sleeve is preferably produced from plastic.
In another embodiment, in order to allow the deformable wall to be exchanged if it is worn, it may be connected to the liquid container by a thread, a clip device, or some other releasable connection.
The features of another embodiment are provided in order to enable the liquid container to be easily removed from the hair-shaping appliance to be filled with a liquid. The liquid container is preferably filled with water, water enriched with fragrances, hair-treating substances, or other materials. A locking device designed in accordance with the principle of a bayonet closure allows the liquid container to be quickly inserted and removed. In the locked position, the locking device releases the liquid container for further displacement in the direction of the evaporating chamber. At least one stub projecting radially on the liquid container initially engages in a recess, when inserted, and is then secured by rotation against dropping out automatically. The liquid container can be moved back and forth within certain limits in the longitudinal direction by means of a further recess adjoining the first recess. Instead of one stub, of course, it is also possible for two or more stubs to be formed on the circumference of the liquid container. Although, in this case, it is also necessary to introduce into the sleeve a corresponding number of recesses, which then cooperate with the respectively associated stub. This improves the guidance of the liquid container.
The features of another embodiment ensure that it is only when the liquid container has been removed from the hair-shaping appliance and the closure cap has been opened that it can be filled with water. The operation of removing the liquid container from the hair-shaping appliance, which is necessary for filling the liquid container, helps to prevent malfunctioning of, and thus possible damage to, the hair-shaping appliance, because a user is not required to hold the entire appliance under a water source during the filling operation. The forced separation of the liquid container from the hair-shaping appliance facilitates handling of the filling operation.In this case, the hair-shaping appliance can be set to one side and the liquid container, on account of it being smaller than the rest of the hair-shaping appliance, can be held more easily under a faucet or a container.
The features of another embodiment ensure that, following actuation of the dosing device, the liquid container is automatically moved back into its starting position by the force of the compression spring as soon as the actuating force applied to the elastic wall by a user decreases.
According to the features of another embodiment, the compression spring, in addition to serving as a restoring spring for the liquid container, also performs a retaining and sealing function. A sealing ring mounted on an external diameter of the compression spring butts with sealing action against the liquid container and seals the evaporator chamber in relation to the bore formed in the insulating sleeve and to the liquid container. The sealing ring butts with sliding action in the bore of the insulating sleeve to seal the evaporator chamber when the liquid container is displaced.
The features of another embodiment ensure that, if a water droplet is actually slung out of the evaporator chamber, it is stopped on the hot felt ring where it evaporates and then penetrates the felt ring in the form of steam. This prevents the functioning of the catalyst from being disturbed.